Process of producing an insulating material.



UNITED STATES PATENT OFFICE.

WLADIMIR SCHEWELIN, F MOSCOW, RUSSIA.

PROCESS OF PRODUCING AN INSULATING MATERIAL.

Be it known that I, VLADIMIR SOHEWELIN, a subject of the Emperor of Russia, and a resident of the city of Moscow, Russia, have invented new and useful Improvements in Processes of Producing an Insulating Material, of which the following is a specification.

This invention relates to an improved process of manufacturing a known insulating filling material for refrigerating cars, passenger cars, acoustic insulation purposes, and the like, which insulating material consists of layers of flax or hemp with interposed sheets of paper, pasteboard, or the like, the layers being thread sewn in difi'erent directions.

Hitherto, in refrigerating apparatus, an insulating filling substance known as linofelt, has been used, which consists of two layers of water-proof pasteboard, between which is interposed, a thin layer of fine and short flax that contains a considerable quantity of shive.

The filling material made in accordance with the present invention is similar in appearance to that above described, but it possesses a higher power of insulation, greater purity, is not so liable to be attacked by mold, and offers greater resistance to shocks and vibrations, to which the filling layers of refrigerating and passenger cars are particularly subjected.

In carrying out my invention, the fibrous flax material, and the threads to be used in sewing together the several flax layers of the filling material, are washed in a washing machine at a temperature not below 30 to 40 degrees centigrade, dried by centrifugal force, then lixiviated in a mixture of caustic Specification of Letters Patent.

Patented July 31, 191 '7.

Application filed July 9, 1914. Serial No. 849,880.

soda and calcined soda, and thereupon sub jected about three times to a washing opera tion in hot water, disinfecting and non-odor developing materials, such as borax, perborate, acetate of alumina, and the like, being added during the last washing operation. Finally, the material is subjected to the action of centrifugal force and quickly dried by the addition of formalin vapors.

This treatment results in a pure flax material which is entirely devoid of odor, and is not influenced by moisture or attacked by mold; it yields a large quantity of fiber and possesses superior properties of insulation and resistance against shocks and vibrations.

The fibrous material produced as described, is formed into a number of layers between which are interposed, sheets of paper, parchment or pasteboard. The com posite body thus obtained, is placed between covers of water-proof pasteboard, or textile material, and is connected thereto by means of longitudinal and cross seams.

It is to be understood that my process is not restricted to the use of flax or hemp, as any other fibrous material of similar physical properties may be used instead.

I claim:

A process of treating fiber for use in an insulating filling material which consists in washing the fibrous substance, drying the same, lixiviating it in a mixture of caustic and calcined soda, again washing it in hot water together with disinfecting and nonodor developing substances, and drying it by the addition of formalin vapors.

WLADIMIR SCHEWELIN.

Witnesses:

GHBIs'r. ERrUR'r, LYDIA RtSLL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner 0! Patents, Washington, D. G. 

